C. elements found in the have similar chemical properties.

Each row of the periodic table is called a period and each column of the periodic table is called a group (or family). Some groups have specific names like the halogens or noble gases. Elements within the same period or group have similar properties

The process is c.convection

Each calcium ion has a charge of +2, which can also be written as ca2+. if those ions move out of the neuron and no other ions are moving, the neuron would lose the positive charge associated with those ions and become more negatively charged.